8824/0 Myofibroma

Definitions

Connective, subcutaneous and other soft tissues

ICD-O-3 topography code:

C49

Myofibroma (or myofibromatosis in the case of multicentric lesions) is a benign condition arising within soft tissue or bone, histologically characterized by contractile myoid cells arranged around thin-walled blood vessels, with a nodular or multinodular growth pattern. Plump, spindle shaped myofibroblasts are generally located in the periphery of the lesion and arranged in short fascicles or whorls, while less differentiated cells predominate in the centre of the nodules 1

Myofibroma of soft tissue affects the cutaneous/subcutaneous tissues of head and neck, trunk, and extremities. Myofibromatosis also arises in the deep soft tissues and at visceral locations. Lesions in dermis and subcutaneous tissue are generally better defined than those in the deep soft tissues and viscera.
Myofibroma/myofibromatosis occurs in all age groups with a predilection for males. Myofibromas may regress spontaneously. Recurrence after excision is rare. The prognosis for visceral lesions depends on extent and location 2